If `x`
is a rational number and `y`
is an irrational number, then
both `x\ +\ y\ a n d\ x y`
are
necessarily rational
both `x\ +\ y\ a n d\ x y`
are
necessarily irrational
`x y`
is
necessarily irrational, but `x\ +\ y`
can be
either rational or irrational
`x\ +\ y`
is
necessarily irrational, but `x y`
can be
either rational or irrational
Text Solution
Verified by Experts
No. (xy) is necessarily an irrational only when `x ne O`. Let x be a non-zero rational and y be an irrational. Then , we have to show that xy be an irrational . If possible, let xy be a rational number. Since, quotient of two non- zero rational so , `((xy)/x)` is a rational number ` Rgihtarrow ` Y is a rational number . But, this contradicts the fact that y is an irrational number. thus, our supposition is wrong. Hence , xy is an irrational number. but, when x=0, then xy=0, rational number.
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